Offensive Rebounding and the Celtics Off-Season

Ryan Parker is doing some serious freaking work over at his site, the Basketball Geek. Over the weekend, he posted a whole bunch of data measuring the likelihood of a team scoring a basket on a given possession based on how that possession began. In other words, how much more likely is a team to score after they force a turnover versus after giving up a two-point field goal?

Every piece of data he finds is interesting, even if some of them are expected. For instance: It’s not a surprise that teams score a lot more easily on a possession that begins with a steal or another kind of turnover, but the difference is really huge–nearly 20 percentage points in eFG% when compared to a possession that begins off an opponent’s made basket. One way to interpret that piece of data is to think that forcing turnovers on defense and avoiding them on offense are crucial to a team’s success. But then you look at the Celtics, a team that coughs the ball up at an alarming rate, or the Magic and the Spurs, teams that are “bad” at forcing turnovers but rarely commit them, and you begin to wonder if excelling at one end of the turnover spectrum is enough to win. Or you wonder how amazing the Suns offense could have been, considering they had the fifth-worst turnover rate in the league on offense and the tenth-worst rate of forcing them on defense.

There was one other way to begin a possession that had a really big impact on the likelihood of a hoop: Offensive rebounding. It was a clear #2 behind turnovers, and, interestingly, helped a team’s three-point percentage more than any other variable. (See the second graph). This makes sense, obviously–an ORB can lead to a quick put-back or a kick out for an open three while the defense is scrambling to react.

The quick summary is that there appears to be some evidence that an offensive rebound might be a slightly more valuable thing for an individual to get than a defensive rebound, since one of your teammates is far more likely to grab that defensive board than the offensive board. (The smart people call this the Law of Diminishing Returns; if you want to learn more, click on the link at the beginning of the last paragraph).

As I’ve written before, Davis’ rank there surprised me, because he’s an awful defensive rebounder. Perhaps the presence of a defensive-rebounding machine (KG) has a little to do with that, but the gap between Davis’ offensive rebounding and defensive rebounding is one of the largest in the NBA.

Do these ORB numbers mean the Celtics should make re-signing both guys a bigger priority than it already is?

Ideally, the answer would be “Hell, yes!” but, alas, reality intrudes. In Leon’s case, the reality is his newest knee injury. Will he be explosive enough after yet another surgery to remain an elite offensive rebounder?

In Baby’s case, the reality is money. If he wants the mid-level exception, the Celtics probably have to let him go. As I said last week (piggy-backing off of Roy Hobbs at CB), the C’s likely have about $10 million to spend this off-season, including the mid-level exception, which will be someplace between $5 and $5.5 million. Since the C’s can re-sign Davis without using the mid-level (they have his Early Bird rights), the best outcome for the C’s is to sign Davis for significantly less than the mid-level (maybe $3 or $3.5 million/year). Will he agree to that?

Just for fun, after the jump I’ll list the career and most-recent-season offensive rebounding rates for the free agent forwards (and one center) I like best. (And, obviously, many of these forwards are valuable because of skills other than defensive rebounding–we’re going to take a look at most of them in detail individually in the weeks to come).

Hmmm… This stat seems incomplete at first glance. I’d think that rebounding one’s own miss really just negates a previous mistake, and likely doesn’t do much for any one else efg%. Baby is a pretty good offensive rebounder, but a lot of his offensive boards are gained by getting the ball stuffed back in his face.

All offensive boards are not equal, and the general positive of offensive rebounding cannot be attributed to every offensive rebounder.

Ben

I think you’re missing the fact that a defensive rebound prevents the opponent from getting an offensive rebound. I think I’d rather be a good defensive rebounding team versus offensive if I had to choose.

http://www.celticshub.com Zach Lowe

Believe me, I understand the importance of DRBs–if you look at the best teams in the NBA in any given season, invariably, they are all clustered in the top 10 in DRB percentage. Protecting the defensive glass is one of the first steps toward becoming a good team.

This post is just meant to throw out questions/discussion topics rather than make any final decision. Just sort of throwing something out there.

For offensively challeneged players, not having to worry about a defender focused on you can free you up into finding good position for the impending offensive boards.

http://perkisabeast.com/blog Carl Spackler

Doesn’t even mention that the majority of Baby’s Offensive Rebounds come off his own putrid shot selection/inability to finish around the hoop.

Davis is also a sever liability on the Defensive End, so most of his offensive totals are a wash with his negatives on D.

http://celticshub.com Zach

@Carl: You were the one who wrote that awesome “LeBron never gets a foul called on him” to TH, weren’t you? Good stuff.

Yes, I’m sure Baby gets his share of ORBs off his own misses. He put up even better ORB numbers last season, when he was taking fewer Js, so it makes sense. But he may also have a knack for using his body to create space as an offensive rebounder. Only time will tell.

Just one more thing to consider in the evaluation of Big Baby.

http://loscy.wordpress.com CelticsFanatic

I don’t have a good feeling about Powe. He will miss at least 1/3 of the season, and I just don’t know. I hope we re-sign him because he is quite possibly the BEST human being in the world, and he stands for all that is right in sports and in humanity, and the dude can get offensive boards and play pretty solid post defense. His game is really coming together and he’s adding all sorts of moves to his offensive game… But damn. It doesn’t make sense financially at all. If Powe is willing to take a discount to stay with the Celts, I can see the front office cutting him a 2 year deal for just over $1.2 million per.

I wouldn’t mind seeing TA and Scal traded to a team looking for depth off the bench and some additional role players. TA and Scal could be packaged together to help a team defensively. In our system, TA can’t get 8-10 touches to put up 12 points in a game and be a reliable perimeter defender; but somewhere else, in another system, TA could help improve a bench with his athleticism in an uptempo style game: Phoenix? Golden State? New York? Scal is the king of intangibles on the court: smart fouls on defense, taking charges, hustling for loose balls, guarding positions 3-5, and helping to stretch the court out a bit with his ability to knock down some outside shots. Packaged together, they can be very appealing to a team looking to dump one player earning $5-6 million: the total salary between Scal and TA.

I’m pretty convinced that TA will be moved. After the whole Chicago fiasco of the death threats against him and his inability to stay healthy and him having a basketball IQ of a acorn, it’s time the Celts cut ties with him. We’ve given him time, but it’s time to walk away from the table. What should we get in return? How about a veteran point guard? Or a veteran center? Either one. Size would be preferable, but a decent back up for Rondo has to be found somewhere at some point. These are two roles we NEED to fill, and it would be great to see it taken care of by dumping TA and unfortunately saying goodbye to Scal. Let’s say we go with the size: we trade TA and Scal for a BIG. Done. Taken care of.

Thoughts??

Jeff

One thing not really mentioned about defensive or offensive rebounding stats above is the way offensive penetration and/or poor defensive rotation impact those numbers. When teams don’t have to help on a penetrator — when a Paul Pierce can stop a Kobe one-on-one — or double a big man — when Perk can keep Howard away from the hoop — the other defenders are in position to box out and get a DRB. When a Pierce or an Allen forces a double or help on one side of the rim, a Powe or Davis has a free lane to an ORB, if needed (if Pierce and Allen weren’t such great finishers/passers/foul drawers, Davis might be an even better ORBer.
It’s a team game, and these stats work synergystically with other stuff.